Can't get LG 4K monitor to run at 1080p HiDPI

https://i.imgur.com/TREJEeJ.png

CPU is 8700k, iGPU only. The monitor (27UL850) is driven using HDMI cable, the motherboard doesn't have DP. I'm currently running at 1080p but it's not HiDPI because it looks more blurry than in Windows 10.

I tried sudo defaults write /Library/Preferences/com.apple.windowserver.plist DisplayResolutionEnabled -bool true

at Terminal but can only get HiDPI at 1280x720, 960x540, 800x450.

Is there anything else for me to try.